Device and method of performing an access control

ABSTRACT

A communication device for performing an access control comprises at least one storage device and at least one processing circuit coupled to the at least one storage device. The at least one storage device stores, and the at least one processing circuit is configured to execute instructions of: detecting an access attempt; obtaining an access category corresponding to the access attempt; and performing an access barring check corresponding to the access attempt according to the access category and at least one access barring parameter.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/616,433 filed on Jan. 12, 2018, which is incorporated herein byreference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a communication device and a methodused in a wireless communication system, and more particularly, to acommunication device and a method of handling an access control.

2. Description of the Prior Art

A long-term evolution (LTE) system supporting the 3rd GenerationPartnership Project (3GPP) Rel-8 standard and/or the 3GPP Rel-9 standardare developed by the 3GPP as a successor of the universal mobiletelecommunication system (UMTS) for further enhancing performance of theUMTS to satisfy increasing needs of users. The LTE system includes a newradio interface and a new radio network architecture that provides highdata rate, low latency, packet optimization, and improved systemcapacity and coverage. In the LTE system, a radio access network knownas an evolved universal terrestrial radio access network (E-UTRAN)includes at least one evolved Node-B (eNB) for communicating with atleast one user equipment (UE), and for communicating with a core networkincluding a mobility management entity (MME), a serving gateway (SGW),an access and mobility management function (AMF), a user plane function(UPF), etc., for a Non-Access Stratum (NAS) control.

A LTE-advanced (LTE-A) system, as its name implies, is an evolution ofthe LTE system. The LTE-A system targets faster switching between powerstates, improves performance at the coverage edge of an eNB, increasespeak data rate and throughput, and includes advanced techniques, such ascarrier aggregation (CA), coordinated multipoint (CoMP)transmissions/reception, uplink (UL) multiple-input multiple-output(UL-MIMO), licensed-assisted access (LAA) (e.g., using LTE), etc. For aUE and an eNB to communicate with each other in the LTE-A system, the UEand the eNB must support standards developed for the LTE-A system, suchas the 3GPP Rel-1× standard or later versions.

A fifth generation (5G) system (5GS) (e.g., 5G new radio access network(5G-NR)) is an evolution of a continuous mobile broadband process tomeet the requirements of 5G as introduced by International MobileTelecommunications (IMT)-2020. The 5GS may include a radio accessnetwork (RAN) and a core network (CN). The RAN may include at least onebase station (BS). The at least one BS may include an evolved Node-B(eNB) or a 5G Node-B (gNB), for communicating with at least one UE andfor communicating with the CN. The CN may include a MME, a SGW, an AMF,a UPF, etc., for a NAS control.

A network (e.g., the above E-UTRAN or 5G-NR) may apply an access controlto a UE for barring an application newly initiated by the UE, e.g., whenthe network is in congestion. However, the application may bypass theaccess control, when the application is mapped to an existing Quality ofService (QoS) flow. Accordingly, the application still may trigger an ULtransmission toward the network, and the congestion may be aggravated.

Thus, how to handle the access control is an important issue to besolved.

SUMMARY OF THE INVENTION

The present invention therefore provides a method and relatedcommunication device for handling an access control to solve theabovementioned problem.

A communication device for performing an access control comprises atleast one storage device and at least one processing circuit coupled tothe at least one storage device. The at least one storage device stores,and the at least one processing circuit is configured to executeinstructions of: detecting an access attempt; obtaining an accesscategory corresponding to the access attempt; and performing an accessbarring check corresponding to the access attempt according to theaccess category and at least one access barring parameter.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a wireless communication systemaccording to an example of the present invention.

FIG. 2 is a schematic diagram of a communication device according to anexample of the present invention.

FIG. 3 is a flowchart of a process according to an example of thepresent invention.

FIG. 4 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 5 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 6 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 7 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 8 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 9 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 10 is a schematic flowchart of performing an access controlaccording to an example of the present example.

FIG. 11 is a schematic diagram of a structure of an access categoryinformation according to an example of the present example.

FIG. 12 is a schematic diagram of a structure of an access categoryinformation according to an example of the present example.

FIG. 13 is a schematic diagram of a structure of an access categoryinformation according to an example of the present example.

FIG. 14 is a schematic diagram of a structure of an access barringparameter according to an example of the present example.

FIG. 15 is a schematic diagram of a structure of an access barringparameter according to an example of the present example.

FIG. 16 is a schematic diagram of a structure of an access barringparameter according to an example of the present example.

DETAILED DESCRIPTION

FIG. 1 is a schematic diagram of a wireless communication system 10according to an example of the present invention. The wirelesscommunication system 10 is briefly composed of a network and a pluralityof communication devices. The wireless communication system 10 maysupport a time-division duplexing (TDD) mode, a frequency-divisionduplexing (FDD) mode, a TDD-FDD joint operation mode or alicensed-assisted access (LAA) mode. That is, the network and acommunication device may communicate with each other via FDD carrier(s),TDD carrier(s), licensed carrier(s) (licensed serving cell(s), licensedspectrum(s)) and/or unlicensed carrier(s) (unlicensed serving cell(s),unlicensed spectrum(s)). In addition, the wireless communication system10 may support a carrier aggregation (CA). That is, the network and acommunication device may communicate with each other via multipleserving cells (e.g., multiple serving carriers) including a primary cell(e.g., primary component carrier) and one or more secondary cells (e.g.,secondary component carriers).

Methods of utilizing an unlicensed carrier are various. For example, acommunication system (e.g., the wireless communication system 10) whichincludes at least one base station (BS) may provide a wireless servicevia the unlicensed carrier without an assistance from a licensed servingcell, i.e., the communication system is not a LAA system. Accordingly, acommunication device may communicate with the at least one BS via onlythe unlicensed carrier. In one example, the communication device maycommunicate with more than one BSs (e.g., 2) in a same time period(e.g., dual connectivity). One of the BSs may only be configured withthe unlicensed carrier for the wireless service.

In FIG. 1, the network and the communication devices are simply utilizedfor illustrating the structure of the wireless communication system 10.Practically, the network may be a universal terrestrial radio accessnetwork (UTRAN) including at least one Node-B (NB) in a universal mobiletelecommunications system (UMTS). In another example, the network may bean evolved UTRAN (E-UTRAN) including at least one evolved NB (eNB)and/or at least one relay in a long term evolution (LTE) system, aLTE-Advanced (LTE-A) system or an evolution of the LTE-A system. In oneexample, the network may be a fifth generation (5G) system (5GS) (e.g.,new radio access network (5G-NR)) including at least one a 5G Node-B(gNB).

Furthermore, the network may also include both the UTRAN/E-UTRAN/5G-NRand a CN, wherein the CN may include network entities such as MobilityManagement Entity (MME), Serving Gateway (S-GW), Packet Data Network(PDN) Gateway (P-GW), Self-Organizing Networks (SON) server and/or RadioNetwork Controller (RNC), etc., for a Non-Access Stratum (NAS) control.In other words, after the network receives information transmitted by acommunication device, the information may be processed only by theUTRAN/E-UTRAN/5G-NR and decisions corresponding to the information aremade at the UTRAN/E-UTRAN. Alternatively, the UTRAN/E-UTRAN/5G-NR maytransmit the information to the CN, and the decisions corresponding tothe information are made at the CN after the CN processes theinformation. In addition, the information may be processed by both theUTRAN/E-UTRAN/5G-NR and the CN, and the decisions are made aftercoordination and/or cooperation are performed by the

A communication device may be a user equipment (UE), a low cost device(e.g., machine type communication (MTC) device), a device-to-device(D2D) communication device, a mobile phone, a laptop, a tablet computer,an electronic book, a portable computer system, or combination thereof.In addition, the network and the communication device can be seen as atransmitter or a receiver according to direction (i.e., transmissiondirection), e.g., for an uplink (UL), the communication device is thetransmitter and the network is the receiver, and for a downlink (DL),the network is the transmitter and the communication device is thereceiver.

FIG. 2 is a schematic diagram of a communication device 20 according toan example of the present invention. The communication device 20 may bea communication device or the network shown in FIG. 1, but is notlimited herein. The communication device 20 may include at least oneprocessing circuit 200 such as a microprocessor or Application SpecificIntegrated Circuit (ASIC), at least one storage device 210 and at leastone communication interfacing device 220. The at least one storagedevice 210 may be any data storage device that may store a program code214, accessed and executed by the at least one processing circuit 200.Examples of the at least one storage device 210 include but are notlimited to a subscriber identity module (SIM), read-only memory (ROM),flash memory, random-access memory (RAM), Compact Disc Read-Only Memory(CD-ROM), digital versatile disc-ROM (DVD-ROM), Blu-ray Disc-ROM(BD-ROM), magnetic tape, hard disk, optical data storage device,non-volatile storage device, non-transitory computer-readable medium(e.g., tangible media), etc. The at least one communication interfacingdevice 220 is preferably a transceiver and is used to transmit andreceive signals (e.g., data, messages and/or packets) according toprocessing results of the at least one processing circuit 200.

FIG. 3 is a flowchart of a process 30 according to an example of thepresent invention. The process 30 may be utilized in a communicationdevice (e.g., the communication device shown in FIG. 1) including anapplication layer, a NAS layer and a radio resource control (RRC) layer,to perform an access control. The process 30 may be compiled into theprogram code 214 and includes the following steps:

Step 300: Start.

Step 302: Detect an access attempt.

Step 304: Obtain an access category corresponding to the access attempt.

Step 306: Perform an access barring check corresponding to the accessattempt according to the access category and at least one access barringparameter.

Step 308: End.

According to the process 30, the communication device may detect an(e.g., UL) access attempt. The communication device may obtain (e.g.,determine) an access category corresponding to the access attempt. Then,the communication device may perform an access barring checkcorresponding to the access attempt according to the access category andat least one access barring parameter. That is, any access attemptdetected by the communication device does not bypass the access barringcheck. Thus, the issue of the congestion resulted from bypassing theaccess control can be solved.

Realization of the process 30 is not limited to the above description.The following examples may be applied for realizing the process 30.

In one example, the access attempt may be detected by (e.g., in) the NASlayer. In one example, the access attempt may be detected by (e.g., in)the NAS layer according to (e.g., by using) a QoS rule, wherein the QoSrule may include a QoS rule identity (ID), a QoS Flow ID (QFI),associated QoS parameters (e.g., 5G QoS Identifier (5QI), Guaranteed BitRate (GBR), and Maximum Bit Rate (MBR)), at least one packet filterand/or a precedence value. Each of the at least one packet filter mayinclude a source IP address, a destination IP address, a source portnumber, a destination port number, a protocol ID and/or a type ofservice (ToS) or a Differentiated Services Code Point (DSCP). Eachpacket received from a higher layer (e.g., the application layer or theNAS layer) may be mapped to a QoS flow according to the QoS rule. Thatis, the NAS layer maps (e.g., compares) the access attempt to at leastone existing QoS flow by using the QoS rule. A new access attempt may bedetected according to the QoS rule when a packet does not belong to anyexisting (e.g., preceding) access attempt (e.g., at least one value ofthe packet filter parameters of the access attempt is different fromthat of the existing access attempts). In one example, the accessattempt may be initiated (e.g., detected) by (e.g., in) the applicationlayer or the NAS layer. In one example, the access attempt may beinitiated by at least one of service(s), application(s) and function(s)of the communication device.

In one example, the access category may be obtained (e.g., determined)by (e.g., in) the NAS layer (e.g., according to a first access categoryinformation (e.g., a first access categorizing rule and/or a firstaccess category mapping table) received from a CN (e.g., an AMF, anoperations, administration, and maintenance (OAM))). In one example, theaccess category may be obtained (e.g., determined) by (e.g., in) the NASlayer (e.g., according to a second access category information (e.g., asecond access categorizing rule and/or a second access category mappingtable) maintained (e.g., stored, predetermined) in the communicationdevice (e.g., in a Universal Subscriber Identity Module (USIM) or anon-vulnerable memory of the communication device)). In one example, theaccess category may include at least one access identity (ID) associatedwith the access attempt. In one example, the first access categoryinformation may include a first correspondence between a first pluralityof access attempts and a first plurality of access categories. Thesecond access category information may include a second correspondencebetween a second plurality of access attempts and a second plurality ofaccess categories. In one example, the first access category informationand/or the second access category information may be predefined in the3GPP standard (e.g., a Table of 5GS Access Categories of TS 22.261). Thefirst plurality of access attempts and/or the second plurality of accessattempts may be predefined in the 3GPP standard (e.g., Type of accessattempt in the Table of 5GS Access Categories of TS 22.261). The firstplurality of access categories and/or the second plurality of accesscategories may be predefined in the 3GPP standard (e.g., Access categorynumber in the Table of 5GS Access Categories of TS 22.261). In oneexample, the first access category information and the second accesscategory information may be the same or different.

In one example, the communication device may transmit a firstnotification message/indication (e.g., control plane (CP)message/indication) for notifying that the access attempt (e.g., theaccess attempt identity) has been detected to the RRC layer from the NASlayer. That is, the first notification message/indication is transmittedfrom the NAS layer to the RRC layer. In one example, the firstnotification message may or may not include the access category. In oneexample, the access category may or may not include the at least oneaccess ID associated with the access attempt.

In one example, the access category may be obtained (e.g., determined)by (e.g., in) the RRC layer (e.g., according to a third access categoryinformation (e.g., a third access categorizing rule and/or a thirdaccess category mapping table)), when the first notification messagedoes not include any access category. In one example, the accesscategory may be obtained (e.g., determined) by (e.g., in) the RRC layeraccording to a third access category information (e.g., a third accesscategorizing rule and/or a third access category mapping table), whenthe access attempt is initiated by the RRC layer. The third accesscategory may be maintained (e.g., stored) in the communication device(e.g., in a USIM or a non-vulnerable memory of the communicationdevice). In one example, the first access category information, thesecond access category information and the third access categoryinformation may be the same or different. In one example, the NAS layerand the RRC layer may obtain the access category according to (e.g., byusing) the same (e.g., single) access categorizing rule and the sameaccess category mapping table. In one example, the NAS layer and the RRClayer may obtain the access category according to (e.g., by using)different (e.g., separate) access categorizing rules and the same accesscategory mapping table.

In one example, the access barring check may be performed by (e.g., in)the RRC layer, e.g., when the access category is transmitted (e.g.,notified or indicated) by the NAS layer or the application layer.

In one example, the communication device may transmit a secondnotification message/indication (e.g., CP message/indication) fornotifying a result of the access barring check to the NAS layer from theRRC layer. That is, the second notification message/indication istransmitted from the RRC layer to the NAS layer. In one example, theresult may notify that the access attempt is allowed (e.g., passed). Inone example, the result may notify that the access attempt is barred.Accordingly, the access attempt may be barred for a time period of theaccess attempt being barred. The time period of the access attempt beingbarred may be predetermined in the at least one access barringparameter. In one example, the communication device may transmit a thirdnotification message/indication for notifying that a barring for theaccess category is (e.g., has been) alleviated to the NAS layer from theRRC layer. That is, the third notification message/indication istransmitted from the RRC layer to the NAS layer.

In one example, the application layer and the NAS layer may be unawareof whether the access barring check is performed (e.g., activated). Inone example, the application layer and the NAS layer do not (e.g., needto) know the time period (e.g., barring time, a start and/or stop timeinstant) of the access attempt being barred. In one example, theapplication layer and the NAS layer may be aware of whether the accessbarring check is performed. In one example, the application layer andthe NAS layer knows the time period (e.g., barring time, a start and/orstop time instant) of the access attempt being barred, when receiving anotification message for notifying a result of the access barring checkand receiving the time period (e.g., barring time, a start and/or stoptime instant) of the access attempt being barred from the RRC layer. Inone example, the application layer and the NAS layer may be unaware ofthe at least one access barring parameter. That is, the applicationlayer and the NAS layer do not (need to) obtain and maintain (e.g.,store) the at least one access barring parameter.

In one example, the at least one access barring parameter may bereceived by (e.g., in) the RRC layer from a network node (e.g., RAN orgNB). In one example, the at least one access barring parameter may bebroadcasted or transmitted by the network node via system information(e.g., system information block (SIB)). In one example, the at least oneaccess barring parameter may be maintained (e.g., stored) in thecommunication device (e.g., in the USIM or a non-vulnerable memory ofthe communication). In one example, the at least one access barringparameter may include at least one of at least one probability of atleast one access attempt (e.g., “nac-BarringFactor”), at least one timeperiod of the at least one access attempt (e.g., “nac-BarringTime”) andat least one identity of the at least one access attempt (e.g.,“nac-ID”), and may include at least one Boolean value of whether toactivating the barring of the at least one access attempt being barred(e.g., “nac-BarringActivate”).

In one example, the access barring check may be performed by theapplication layer or the NAS layer, when the at least one access barringparameter is transmitted (e.g., notified or indicated) to theapplication layer or the NAS layer from the RRC layer. That is, the atleast one access barring parameter is available not only in the RRClayer, but also in the application layer or the NAS layer.

In one example, the communication device may be in a connected mode(e.g., CM_CONNECTED mode or RRC_CONNECTED mode). In one example, thecommunication device may be in an inactive mode or an idle mode.

FIG. 4 is a schematic flowchart of performing an access control in acommunication device 40 according to an example of the present example.The communication device 40 may comprise a higher layer 42 and a RRClayer 44. At Step 400, the higher layer 42 (e.g., an application layeror a NAS layer) may receive a first access category information from aCN (e.g., via an OAM configuration or a NAS layer configuration), or mayretrieve a second access category information in a memory of thecommunication device 40 (e.g., USIM or non-vulnerable memory). At Step402, the higher layer 42 detects a first access attempt of (e.g.,initiated by) the higher layer 42. At Step 404, the higher layer 42obtains a first access category corresponding to the first accessattempt. At Step 406, the higher layer 42 transmits a first notificationmessage with (e.g., including) the first access category, and mayfurther include at least one access identity (ID) associated with thefirst access attempt, to notify the first access attempt to the RRClayer 44. The higher layer 42 may update the second access categoryinformation in the memory according to a third access categoryinformation (e.g., the first access category information) received fromthe CN.

At Step 408, the RRC layer 44 receives at least one access barringparameter from (e.g., transmitted or broadcasted by) a network node(e.g., RAN or gNB), and maintains the at least one access barringparameter (e.g., in the memory). At Step 410, the RRC layer 44 mayinitiate a RRC procedure corresponding to the received (e.g., first)notification message, and may further trigger a second access attempt.The RRC layer 44 may obtain a second access category of the secondaccess attempt initiated by the RRC layer 44, e.g., by performing anaccess to the second access category information maintained in thememory and obtaining the second access category of the second accessattempt according to the second access category information. At Step412, the RRC layer 44 performs a first access barring check according tothe first access category and the at least one access barring parameter,and/or perform a second access barring check according to the secondaccess category and the at least one access barring parameter. At Step414, the RRC layer 44 transmits a second notification message to notifya result of the first and/or second access barring check (e.g., theaccess attempt requested by higher layers, e.g., the first and/or secondaccess attempt) is allowed or barred) to the higher layer 42.

If the NAS layer receives the second notification message for notifyingthe first access attempt is barred from the RRC layer 44, the NAS layermay notify the upper layer 42 (e.g., the application layer or a servicelayer) that the first access attempt is barred if the first accessattempt was initiated by the upper layer 42.

The RRC layer 44 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt), e.g., when the expiry of the time period that the barredaccess attempt and/or the barred access category has been barred, to thehigher layer 42. If the NAS layer receives the third notificationmessage for notifying the alleviation of the barred access attempt fromthe RRC layer 44, the NAS layer may notify the upper layer 42 (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt was initiated by the upper layer 42.

That is, the RRC layer 44 is responsible for performing the first and/orsecond access barring check.

FIG. 5 is a schematic flowchart of performing an access control in acommunication device 50 according to an example of the present example.The communication device 50 may comprise a NAS layer 52 and a RRC layer54. At Step 500, the NAS layer 52 may receive a first access categoryinformation from a CN (e.g., via an OAM configuration or a NAS layerconfiguration), or may retrieve a second access category information ina memory of the communication device 50 (e.g., USIM or non-vulnerablememory). At Step 502, the NAS layer 52 may detect a first access attemptof (e.g., initiated by) an application. At Step 504, the NAS layer 52may initiate a NAS procedure corresponding to the first access attempt(e.g., a Tracking Area Update (TAU) or a UE-initiated NAS transportprocedure), and may further trigger a second access attempt. At Step506, the NAS layer 52 obtains first access categories corresponding tothe access attempts (the first access attempt and the second accessattempt). In one example, the NAS layer 52 may obtain (e.g., select) asecond access category from the first access categories for (e.g.,associated with) a first notification message. At Step 508, the NASlayer 52 triggers a NAS event corresponding to the first accesscategories and the obtained access attempts, and transmits the firstnotification message corresponding to the first access categories andthe obtained access attempts with or without the second access categoryto notify the access attempts to the RRC layer 54. The NAS layer 52 mayupdate the second access category information in the memory according toa third access category information (e.g., the first access categoryinformation) received from the CN.

At Step 510, the RRC layer 54 receives at least one access barringparameter from (e.g., transmitted or broadcasted by) a network node(e.g., RAN or gNB), and maintains the at least one access barringparameter (e.g., in the memory). At Step 512, the RRC layer 54 mayinitiate a RRC procedure corresponding to the received notificationmessage and may further trigger a third access attempt. The RRC layer 54may obtain a third access category of the third access attempt initiatedby the RRC layer 54 (e.g., by performing an access to the second accesscategory information maintained in the memory and obtaining the thirdaccess category(ies) of the access attempts according to the secondaccess category information). At Step 514, the RRC layer 54 performs afirst access barring check according to the second access category andthe at least one access barring parameter, when the second accesscategory is received from the NAS layer 52, and/or performs a secondaccess barring check according to the third access category and the atleast one access barring parameter. At Step 516, the RRC layer 54transmits a second notification message to notify a result of the accessbarring check (e.g., the access attempts requested by higher layers areallowed or barred) to the NAS layer 52. That is, the NAS layer 52 isresponsible for obtaining the first access categories of the accessattempts, and the RRC layer 54 is responsible for performing the firstand/or second access barring check.

If the NAS layer 52 receives the second notification message fornotifying the access attempts are barred from the RRC layer 54, the NASlayer 52 may notify the upper layer (e.g., the application layer or theservice layer) that the access attempts are barred if the accessattempts were initiated by the upper layer.

The RRC layer 54 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt), e.g., when the expiry of the time period that an accessattempt has been barred and/or the barred access category, to the higherlayer. If the NAS layer 52 receives the third notification message fornotifying the alleviation of the barred access attempt from the RRClayer 54, the NAS layer 52 may notify the upper layer (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt was initiated by the upper layer.

Alternatively, at Step 514, the RRC layer 54 obtains a fourth accesscategory of the access attempts initiated by the application layerand/or the NAS layer 52, when the second access category is not receivedfrom the NAS layer 52. The RRC layer 54 performs a third access barringcheck according to the fourth access category and the at least oneaccess barring parameter.

FIG. 6 is a schematic flowchart of performing an access control in acommunication device 60 according to an example of the present example.The communication device 60 may comprise a NAS layer 62 and a RRC layer64. At Step 600, the NAS layer 62 may receive a first access categoryinformation from a CN (e.g., via an OAM configuration or a NAS layerconfiguration), or may retrieve a second access category information ina memory of the communication device 60 (e.g., USIM or non-vulnerablememory). At Step 602, the NAS layer 62 may detect a first access attemptof (e.g., initiated by) an application (or a service). At Step 604, theNAS layer 62 may initiate a NAS procedure corresponding to the firstaccess attempt (e.g., a TAU or a UE-initiated NAS transport procedure),and may further trigger a second access attempt. At Step 606, the NASlayer 62 triggers a NAS event and transmits a first notification messagewith a cause value of the access attempt(s) (the first access attemptand/or the second access attempt) to notify the access attempt(s) to theRRC layer 64. In one example, the cause value associated with the firstnotification message transmitted from the NAS layer 62 to the RRC layer64 may be obtained by the NAS layer 62. The NAS layer 62 may update thesecond access category information in the memory according to a thirdaccess category information (e.g., the first access categoryinformation) received from the CN.

At Step 608, the RRC layer 64 receives at least one access barringparameter from (e.g., transmitted or broadcasted by) a network node(e.g., RAN or gNB), and maintains the at least one access barringparameter (e.g., in the memory). At Step 610, the RRC layer 64 obtains afirst access category(ies) of the access attempt(s), e.g., by performingan access to the second access category information maintained in thememory and obtaining the first access category(ies) of the accessattempt(s) according to the second access category information. At Step612, the RRC layer 64 may initiate a RRC procedure corresponding to thereceived (e.g., first) notification message, and may further trigger athird access attempt. The RRC layer 64 may obtain a second accesscategory of the third access attempt initiated by the RRC layer 64according to (e.g., by using) the second access category information. AtStep 614, the RRC layer 64 performs a first access barring checkaccording to the first access category(ies) and the at least one accessbarring parameter, and/or performs a second access barring checkaccording to the second access category and the at least one accessbarring parameter. At Step 616, the RRC layer 64 transmits a secondnotification message to notify a result of the access barring check(e.g., the access attempt(s) requested by higher layers is allowed orbarred) to the NAS layer 62.

If the NAS layer 62 receives the second notification message fornotifying the access attempt(s) is barred from the RRC layer 64, the NASlayer 62 may notify the upper layer (e.g., the application layer or theservice layer) that the access attempt(s) is barred if the accessattempt(s) was initiated by the upper layer.

The RRC layer 64 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt), e.g., when the expiry of the time period that an accessattempt has been barred and/or the barred access category, to the higherlayer. If the NAS layer 62 receives the third notification message fornotifying the alleviation of the barred access attempt from the RRClayer 64, the NAS layer 62 may notify the upper layer (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt was initiated by the upper layer.

That is, the first access category(ies) of the access attempt(s)initiated by the application layer or the NAS layer 62 is obtained bythe RRC layer 64.

FIG. 7 is a schematic flowchart of performing an access control in acommunication device 70 according to an example of the present example.The communication device 70 may comprise a NAS layer 72 and a RRC layer74. At Step 700, the NAS layer 72 may receive a first access categoryinformation from a CN (e.g., via an OAM configuration or a NAS layerconfiguration), or may retrieve a second access category information ina memory of the communication device 70 (e.g., USIM or non-vulnerablememory). At Step 702, the NAS layer 72 may detect a first access attemptof (e.g., initiated by) an application (or a service). At Step 704, theNAS layer 72 may initiate a NAS procedure corresponding to the firstaccess attempt (e.g., a TAU or a UE-initiated NAS transport procedure),and may further trigger a second access attempt. At Step 706, the NASlayer 72 may obtain first access categories corresponding to the accessattempts (the first access attempt and the second access attempt). Inone example, the NAS layer 72 may obtain (e.g., select) a second accesscategory from the first access categories for a NAS message (or a firstnotification message). At Step 708, the NAS layer 72 triggers the NASmessage (or the first notification message) corresponding to the firstaccess categories and the obtained access attempts with or without thesecond access category to the RRC layer 74. The NAS layer 72 may updatethe second access category information in the memory according to athird access category information (e.g., the first access categoryinformation) received from the CN.

At Step 710, the RRC layer 74 receives at least one access barringparameter from (e.g., transmitted or broadcasted by) a network node(e.g., RAN or gNB), and may maintain the at least one access barringparameter (e.g., in the memory). At Step 712, the RRC layer 74 mayobtain a third access category(ies) of the access attempts (e.g., byperforming an access to the second access category informationmaintained in the memory and obtaining the third access category(ies) ofthe access attempts according to the second access categoryinformation), when the NAS message does not include any access category.At Step 714, the RRC layer 74 may initiate a RRC procedure correspondingto the received message (e.g., the NAS message or the first notificationmessage), and may further trigger a third access attempt. The RRC layer74 obtains a fourth access category of the third access attemptinitiated by the RRC layer 74. At Step 716, the RRC layer 74 performs afirst access barring check according to the second access category andthe at least one access barring parameter, and/or perform a secondaccess barring check according to the third access category(ies) and theat least one access barring parameter, and/or performs a third accessbarring check according to the fourth access category and the at leastone access barring parameter. At Step 718, the RRC layer 74 transmits asecond notification message to notify a result of the access barringcheck (e.g., the access attempts requested by higher layer are allowedor barred) to the NAS layer 72.

If the NAS layer 72 receives the second notification message fornotifying the access attempts are barred from the RRC layer 74, the NASlayer 72 may notify the upper layer (e.g., the application layer or theservice layer) that the access attempts are barred if the accessattempts were initiated by the upper layer.

The RRC layer 74 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt), e.g., when the expiry of the time period that an accessattempt has been barred and/or the barred access category, to the higherlayer. If the NAS layer 72 receives the third notification message fornotifying the alleviation of the barred access attempt from the RRClayer 74, the NAS layer 72 may notify the upper layer (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt were initiated by the upper layer.

Alternatively, at Step 712, the RRC layer 74 may not obtain the thirdaccess category(ies) of the access attempts, when the NAS messageincludes the second access category.

FIG. 8 is a schematic flowchart of performing an access control in acommunication device 80 according to an example of the present example.The communication device 80 may comprise a NAS layer 82 and a RRC layer84. At Step 800, the NAS layer 82 may receive a first access categoryinformation from a CN (e.g., via an OAM configuration or a NAS layerconfiguration), or may retrieve a second access category information ina memory of the communication device 80 (e.g., USIM or non-vulnerablememory). At Step 802, the NAS layer 82 detects a first access attempt of(e.g., initiated by) an application (or a service). At Step 804, the NASlayer 82 may initiate a NAS procedure corresponding to the first accessattempt (e.g., a TAU or a UE-initiated NAS transport procedure) and mayfurther trigger a second access attempt. At Step 806, the NAS layer 82obtains a first access categories corresponding to the access attempts(the first access attempt and the second access attempt). In oneexample, the NAS layer 82 may obtain (e.g., select) a second accesscategory from the first access categories for a first notificationmessage. At Step 808, the NAS layer 82 triggers a NAS eventcorresponding to the first access categories and the obtained accessattempts, transmits the first notification message with the secondaccess category to notify the access attempts to the RRC layer 84, andtransmits an indication to avoid repeating obtaining the first accesscategories and/or the second access category to the RRC layer 84. TheNAS layer 82 may update the second access category information in thememory according to a third access category information (e.g., the firstaccess category information) received from the CN.

At Step 810, the RRC layer 84 receives at least one access barringparameter from (e.g., transmitted or broadcasted by) a network node(e.g., RAN or gNB), and maintains the at least one access barringparameter. At Step 812, the RRC layer 84 may initiate a RRC procedurecorresponding to the received (e.g., first) notification message, andmay further trigger a third access attempt. The RRC layer 84 may obtaina third access category of the third access attempt initiated by the RRClayer 84 (e.g., by performing an access to the second access categoryinformation maintained in the memory and obtaining the third accesscategory of the access attempt according to the second access categoryinformation). At Step 814, the RRC layer 84 performs a first accessbarring check according to the second access category and the at leastone access barring parameter, and/or performs a second access barringcheck according to the third access category and the at least one accessbarring parameter. At Step 816 the RRC layer 84 transmits a secondnotification message to notify a result of the access barring check(e.g., the access attempts requested by higher layers are allowed orbarred) to the NAS layer 82.

If the NAS layer 82 receives the second notification message fornotifying the access attempts are barred from the RRC layer 84, the NASlayer 82 may notify the upper layer (e.g., the application layer or theservice layer) that the access attempts are barred if the accessattempts were initiated by the upper layer.

The RRC layer 84 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt), e.g., when the expiry of the time period that an accessattempt has been barred and/or the barred access category, to the higherlayer. If the NAS layer 82 receives the third notification message fornotifying the alleviation of the barred access attempt from the RRClayer 84, the NAS layer 82 may notify the upper layer (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt was initiated by the upper layer.

That is, the RRC layer 84 is avoided repeating obtaining the accesscategories which has been obtained by the NAS layer 82.

FIG. 9 is a schematic flowchart of performing an access control in acommunication device 90 according to an example of the present example.The communication device 90 may comprise a NAS layer 92 and a RRC layer94. At Step 900, the NAS layer 92 may receive a first access categoryinformation from a CN (e.g., via an OAM configuration or a NAS layerconfiguration), or may retrieve a second access category information ina memory of the communication device 90 (e.g., USIM or non-vulnerablememory). At Step 902, the NAS layer 92 detects a first access attempt of(e.g., initiated by) an application (or a service). At Step 904, the NASlayer 92 may initiate a NAS procedure corresponding to the first accessattempt (e.g., a TAU or a UE-initiated NAS transport procedure) and mayfurther trigger a second access attempt. At Step 906, the NAS layer 92obtains a first access categories corresponding to the access attempts(the first access attempt and the second access attempt). In oneexample, the NAS layer 92 may obtain (e.g., select) a second accesscategory from the first access categories for a NAS message (or a firstnotification message). At Step 908, the NAS layer 92 triggers the NASmessage (or the first notification message) with or without the secondaccess category. The NAS layer 92 may update the second access categoryinformation in the memory according to a third access categoryinformation (e.g., the first access category information) received fromthe CN.

At Step 910, the RRC layer 94 receives at least one access barringparameter from (e.g., transmitted or broadcasted by) a network node(e.g., RAN or gNB), and maintains the at least one access barringparameter in the memory. At Step 912, the RRC layer 94 may obtain athird access category(ies) of the access attempts (e.g., by performingan access to the second access category information maintained in thememory and obtaining the third access category(ies) of the accessattempts according to the second access category information). In oneexample, the RRC layer 94 may initiate a RRC procedure corresponding tothe received message (e.g., the NAS message or the first notificationmessage), and may further trigger a third access attempt. The RRC layer94 may obtain a fourth access category corresponding to the third accessattempt (e.g., according to the second access category informationmaintained in the memory). At Step 914, the RRC layer 94 performs afirst access barring check according to the third access category(ies)and the at least one access barring parameter, and/or performs a secondaccess barring check according to the fourth access category and the atleast one access barring parameter. At Step 916, the RRC layer 94transmits a second notification message to notify a result of the accessbarring check (e.g., the access attempts requested by higher layers areallowed or barred) to the NAS layer 92.

If the NAS layer 92 receives the second notification message fornotifying the access attempts are barred from the RRC layer 94, the NASlayer 92 may notify the upper layer (e.g., the application layer or theservice layer) that the access attempts are barred if the accessattempts were initiated by the upper layer.

The RRC layer 94 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt, e.g., when the expiry of the time period that an access attempthas been barred and/or the barred access category, to the higher layer.If the NAS layer 92 receives the third notification message fornotifying the alleviation of the barred access attempt from the RRClayer 94, the NAS layer 92 may notify the upper layer (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt was initiated by the upper layer.

That is, the third access category(ies) obtained by the RRC layer 94take precedence over (i.e., have a priority higher than) the secondcategory obtained by the NAS layer 92.

FIG. 10 is a schematic flowchart of performing an access control in acommunication device 100 according to an example of the present example.The communication device 100 may comprise a NAS layer 102 and a RRClayer 104. At Step 1000, the NAS layer 102 may receive a first accesscategory information from a CN (e.g., via an OAM configuration or a NASlayer configuration), or may retrieve a second access categoryinformation in a memory of the communication device 100 (e.g., USIM ornon-vulnerable memory). At Step 1002, the NAS layer 102 detects a firstaccess attempt of (e.g., initiated by) an application (or a service). AtStep 1004, the NAS layer 102 may initiate a NAS procedure correspondingto the first access attempt (e.g., a TAU or a UE-initiated NAS transportprocedure) and may further trigger a second access attempt. At Step1006, the NAS layer 102 obtains first access categories corresponding tothe access attempts (the first access attempt and the second accessattempt). At Step 1008, the NAS layer 102 may perform a first accessbarring check according to the first access categories and at least oneaccess barring parameter received from the RRC layer 104. In oneexample, the NAS layer 102 may obtain (e.g., select) a second accesscategory associated with the access attempts, for a NAS message or afirst notification message. At Step 1010, the NAS layer 102 triggers aNAS event and transmits the first notification message with the secondaccess category to the RRC layer 104. At Step 1012, the NAS layer 102may indicate a result of the first access barring check (e.g., theaccess attempts initiated by the application layer or the NAS layer 102are allowed or barred) to the RRC layer 104 in the first notificationmessage. The NAS layer 102 may indicate an exemption indicator to theRRC layer 104 in the first notification message, if the NAS layer 102has performed the first access barring check for the access attempts.The NAS layer 102 may update the second access category information inthe memory according to a third access category information (e.g., thefirst access category information) received from the CN.

At Step 1014, the RRC layer 104 may receive the at least one accessbarring parameter from (e.g., transmitted or broadcasted by) a networknode (e.g., RAN or gNB), and may maintain the at least one accessbarring parameter in the memory. At Step 1016, the RRC layer 104performs a second access barring check according to the second accesscategory (e.g., received from the NAS layer 102 or via the OAMconfiguration) and the at least one access barring parameter, when thefirst notification message was received without an exemption indicator.At Step 1018, if the second access barring check was performed in theRRC layer 104, the RRC layer 104 transmits a second notification messageto notify a result of the second access barring check (e.g., the accessattempts are allowed or barred) to the NAS layer 102 with a backofftime.

If the NAS layer 102 receives the second notification message fornotifying the access attempts are barred from the RRC layer 104, the NASlayer 102 may notify the upper layer (e.g., the application layer or theservice layer) that the access attempts are barred if the accessattempts were initiated by the upper layer.

The RRC layer 104 may transmit a third notification message to notify analleviation of a barred access attempt (e.g., the first and/or secondaccess attempt) and/or a barred access category (e.g., the first and/orsecond access category corresponding to the first and/or second accessattempt), e.g., when the expiry of the time period that an accessattempt has been barred and/or the barred access category, to the higherlayer. If the NAS layer 102 receives the third notification message fornotifying the alleviation of the barred access attempt from the RRClayer 104, the NAS layer 102 may notify the upper layer (e.g., theapplication layer or the service layer) that the barring is alleviatedif the barred access attempt was initiated by the upper layer.

That is, the NAS layer 102 performs the access barring check and the RRClayer 104 performs the other access barring check, respectively (e.g.,separately).

FIG. 11 is a schematic diagram of a structure of an access categoryinformation (e.g., the first and/or second access category informationmentioned above) according to an example of the present example. Theaccess category information may be a NR access category (NAC) managementobject (MO). The NAC MO may include at least one NAC MO instance. Eachof the at least one NAC MO instance may include at least one of a NRaccess category ID, an Application configuration, a NAS procedure infoconfiguration, and a RRC procedure info configuration. The Applicationconfiguration may include at least one of an operating system (OS) ID,and an Application ID list including at least one Application ID. The OSID may further include at least one of an OS version, and theApplication ID list including the at least one Application ID. TheApplication ID may further include at least one Application version. TheOS version may or may not include the Application ID list. The NASprocedure info configuration may include a NAS procedure ID listincluding at least one NAS procedure ID. The RRC procedure infoconfiguration may include an RRC procedure ID list including at leastone RRC procedure ID.

FIG. 12 is a schematic diagram of a structure of an access categoryinformation (e.g., the first and/or second access category informationmentioned above) according to an example of the present example. Theaccess category information may be a NAC MO. The NAC MO may include atleast one of an Application configuration, a NAS procedure infoconfiguration, and a RRC procedure info configuration. The Applicationconfiguration may include at least one of an OS ID, an Application IDlist including at least one Application ID, and a NR access category ID.The OS ID may further include at least one of an OS version, and theApplication ID list including the at least one Application ID. TheApplication ID may further include at least one Application version. TheOS version may or may not include the Application ID list including theat least one Application ID. The NAS procedure info configuration mayinclude at least one of an NAS procedure ID list including at least oneNAS procedure ID, and the NR access category ID. The RRC procedure infoconfiguration include at least one of an RRC procedure ID list includingat least one RRC procedure ID, and the NR access category ID.

FIG. 13 is a schematic diagram of a structure of an access categoryinformation (e.g., the first and/or second access category informationmentioned above) according to an example of the present example. Theaccess category information may be a NAC MO. The NAC MO may include atleast one of an Application configuration, a NAS procedure infoconfiguration, and a RRC procedure info configuration. The Applicationconfiguration may include at least one of an OS ID, an Application IDlist including at least one Application ID, and a NR access category ID.The OS ID may further include at least one of an OS version, and theApplication ID list including the at least one Application ID. TheApplication ID may further include at least one Application version. TheOS version may or may not include the Application ID list including theat least one Application ID. The NAS procedure info configuration may ormay not include an NAS procedure ID list including at least one NASprocedure ID. Each of the at least one NAS procedure ID may or may notinclude a Boolean value indicating whether an access attempt of the NASprocedure is barred. The RRC procedure info configuration may or may notinclude an RRC procedure ID list including at least one RRC procedureID. Each of the at least one RCC message ID may or may not include aBoolean value indicating whether an access attempt of the RRC procedureis barred.

FIG. 14 is a schematic diagram of a structure of an access barringparameter (e.g., the at least one access barring parameter mentionedabove) according to an example of the present example. The accessbarring parameter may include a “nac-barringInfoSequence”, which may bea RRC-based access barring parameter. The “nac-barringInfoSequence” mayinclude 2 sub-sequences. The first sub-sequence may be a“nac-BarringForCauseNameList”, which may include a“nac-BarringForCauseName” indicating an access category, a “nac-ID”indicating at least one access identity corresponding to the accesscategory, and a “nac-BarringActivate” represented by at least oneBoolean value indicating whether to activate the at least one accessidentity. Accordingly, barring information corresponding to the accesscategory may be obtained according to the first sub-sequence of theaccess barring parameter. The second sub-sequence may be a“nac-BarringForRRCList”, which may include a “nac-ID” indicating anaccess identity, a “nac-BarringFactor” indicating a barring probabilitycorresponding to the access identity, a “nac-BarringTime” indicating abarring time period corresponding to the access identity, and a“nac-BarringActivate” represented by a Boolean value indicating whetherto activate the access identity. Accordingly, barring informationcorresponding to the access identity may be obtained according to thesecond sub-sequence of the access barring parameter.

FIG. 15 is a schematic diagram of a structure of an access barringparameter (e.g., the at least one access barring parameter mentionedabove) according to an example of the present example. The accessbarring parameter may include a “nac-barringInfoSequence”, which may bea RRC-based access barring parameter. The “nac-barringInfoSequence” mayinclude a first sub-sequence “nac-BarringForCauseNameList”, which mayinclude a “nac-BarringForCauseName” indicating an access category, a“nac-IDList” including at least one sequence of a “nac-ID” and a“nac-BarringActivate”. The “nac-ID” indicates the access identitycorresponding to the access category, and the “nac-BarringActivate”represented by at least one Boolean value indicates whether to subjectthe at least one access identity associated with the “nac-ID” to accessbarring check. Accordingly, barring information corresponding to theaccess category may be obtained according to the first sub-sequence ofthe access barring parameter. The “nac-barringInfoSequence” may includea second sub-sequence “nac-BarringForRRCList”, which may include a“nac-IDList” including at least one sequence of a “nac-ID”, a“nac-BarringActivate”, a nac-BarringFactor, and a nac-BarringTime. The“nac-ID” indicates an access identity, the “nac-BarringFactor” indicatesa barring probability corresponding to the access identity, the“nac-BarringTime” indicates a barring time period corresponding to theaccess identity, and the “nac-BarringActivate” represented by a Booleanvalue indicates whether to subject the access identity associated withthe “nac-ID” to access barring check. Accordingly, barring informationcorresponding to the access identity may be obtained according to thesecond sub-sequence of the access barring parameter.

FIG. 16 is a schematic diagram of a structure of an access barringparameter (e.g., the at least one access barring parameter mentionedabove) according to an example of the present example. The accessbarring parameter may include a “nac-barringInfoSequence”, which may bea layer-specific access barring parameter. The “nac-barringInfoSequence”may include 4 sub-sequences.

The first sub-sequence may be a “nac-BarringForCauseNameList”, which mayinclude a “nac-BarringForCauseName” indicating an access category, a“nac-IDList” including at least one sequence of a “nac-ID”, a“nac-BarringActivate”, and may include a “nac-BarringFactor”, and a“nac-BarringTime”. The “nac-ID” indicates at least one access identitycorresponding to the “nac-BarringForCauseName”, and a“nac-BarringActivate” represented by at least one Boolean valueindicates whether to subject the access identity associated with the“nac-ID” to access barring check. Accordingly, barring informationcorresponding to the access category may be obtained according to thefirst sub-sequence of the access barring parameter. The firstsub-sequence may be shared by each layer of the communication device.The second sub-sequence may be a “nac-BarringForApplicationList”, whichmay include a “nac-IDList” including at least one sequence of a“nac-ID”, a “nac-BarringFactor”, a “nac-BarringTime”, and“nac-BarringActivate”. The “nac-ID” indicates an access identity, a“nac-BarringFactor” indicates a barring probability corresponding to theaccess identity, a “nac-BarringTime” indicates a barring time periodcorresponding to the access identity, and a “nac-BarringActivate”represented by a Boolean value indicates whether to subject the accessidentity associated with the “nac-ID” to access barring check, barringinformation corresponding to the access identity of an application layermay be obtained according to the second sub-sequence of the accessbarring parameter.

The third sub-sequence may be a “nac-BarringForNASList”, which mayinclude a “nac-IDList” including at least one sequence of a “nac-ID”, a“nac-BarringActivate”, a “nac-BarringFactor”, and a “nac-BarringTime”.The “nac-ID” indicates an access identity, a “nac-BarringFactor”indicates a barring probability corresponding to the access identity, a“nac-BarringTime” indicates a barring time period corresponding to theaccess identity, and a “nac-BarringActivate” represented by a Booleanvalue indicates whether to subject the access identity associated withthe “nac-ID” to access barring check. Accordingly, barring informationcorresponding to the access identity of a NAS layer may be obtainedaccording to the third sub-sequence of the access barring parameter. Thefourth sequence may be a “nac-BarringForRRCList”, which may include a“nac-IDList” including at least one sequence of a “nac-ID”, a“nac-BarringActivate”, a “nac-BarringFactor”, and a “nac-BarringTime”.The “nac-ID” indicates an access identity, a “nac-BarringFactor”indicates a barring probability corresponding to the access identity, a“nac-BarringTime” indicates a barring time period corresponding to theaccess identity, and a “nac-BarringActivate” represented by a Booleanvalue indicates whether to subject the access identity associated withthe “nac-ID” to access barring check. Accordingly, barring informationcorresponding to the access identity of a RRC layer may be obtainedaccording to the fourth sub-sequence of the access barring parameter.

It should be noted that although the above examples are illustrated toclarify the related operations of corresponding processes. The examplescan be combined and/or modified arbitrarily according to systemrequirements and/or design considerations.

Those skilled in the art should readily make combinations, modificationsand/or alterations on the abovementioned description and examples. Theabovementioned description, steps and/or processes including suggestedsteps can be realized by means that could be hardware, software,firmware (known as a combination of a hardware device and computerinstructions and data that reside as read-only software on the hardwaredevice), an electronic system, or combination thereof. An example of themeans may be the communication device 20.

Examples of the hardware may include analog circuit(s), digitalcircuit(s) and/or mixed circuit(s). For example, the hardware mayinclude ASIC(s), field programmable gate array(s) (FPGA(s)),programmable logic device(s), coupled hardware components or combinationthereof. In another example, the hardware may include general-purposeprocessor(s), microprocessor(s), controller(s), digital signalprocessor(s) (DSP(s)) or combination thereof.

Examples of the software may include set(s) of codes, set(s) ofinstructions and/or set(s) of functions retained (e.g., stored) in astorage unit, e.g., a computer-readable medium. The computer-readablemedium may include SIM, ROM, flash memory, RAM, CD-ROM/DVD-ROM/BD-ROM,magnetic tape, hard disk, optical data storage device, non-volatilestorage unit, or combination thereof. The computer-readable medium(e.g., storage unit) may be coupled to at least one processor internally(e.g., integrated) or externally (e.g., separated). The at least oneprocessor which may include one or more modules may (e.g., be configuredto) execute the software in the computer-readable medium. The set(s) ofcodes, the set(s) of instructions and/or the set(s) of functions maycause the at least one processor, the module(s), the hardware and/or theelectronic system to perform the related steps.

Examples of the electronic system may include a system on chip (SoC),system in package (SiP), a computer on module (CoM), a computer programproduct, an apparatus, a mobile phone, a laptop, a tablet computer, anelectronic book or a portable computer system, and the communicationdevice 20.

To sum up, the present invention provides a method and relatedcommunication device for performing the access control. Accordingly, anyaccess attempt detected by the communication device does not bypass theaccess barring check. Thus, the issue of congestion resulting frombypassing the access control can be solved.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A communication device comprising an applicationlayer, a Non-Access-Stratum (NAS) layer and a radio resource control(RRC) layer, for performing an access control, comprising: at least onestorage device; and at least one processing circuit, coupled to the atleast one storage device, wherein the at least one storage devicestores, and the at least one processing circuit is configured to executeinstructions of: detecting an access attempt; obtaining an accesscategory corresponding to the access attempt; and performing an accessbarring check corresponding to the access attempt according to theaccess category and at least one access barring parameter; wherein theaccess attempt is detected by the NAS layer.
 2. The communication deviceof claim 1, wherein the access category comprises at least one accessidentity (ID) associated with the access attempt.
 3. The communicationdevice of claim 1, wherein the access category is obtained by the NASlayer.
 4. The communication device of claim 1, wherein the instructionsfurther comprise: transmitting a first notification message fornotifying that the access attempt has been detected to the RRC layerfrom the NAS layer.
 5. The communication device of claim 4, wherein thefirst notification message comprises the access category.
 6. Thecommunication device of claim 5, wherein the access category comprisesat least one access ID associated with the access attempt.
 7. Thecommunication device of claim 4, wherein the access category is obtainedby the RRC layer, when the first notification message does not compriseany access category.
 8. The communication device of claim 1, wherein theaccess barring check is performed by the RRC layer.
 9. The communicationdevice of claim 8, wherein the instructions further comprise:transmitting a second notification message for notifying a result of theaccess barring check to the NAS layer from the RRC layer.
 10. Thecommunication device of claim 9, wherein the instructions furthercomprises: transmitting a third notification message for notifying thata barring for the access category is alleviated to the NAS layer fromthe RRC layer.
 11. The communication device of claim 1, wherein the atleast one access barring parameter is received by the RRC layer from anetwork node.
 12. The communication device of claim 1, wherein the atleast one access barring parameter comprises at least one of at leastone probability of at least one access attempt, at least one time periodof the at least one access attempt, and at least one identity of the atleast one access attempt.
 13. The communication device of claim 1,wherein the access barring check is performed by the application layeror the NAS layer, when the at least one access barring parameter istransmitted to the application layer or the NAS layer from the RRClayer.
 14. The communication device of claim 1, wherein thecommunication device is in a connected mode, an inactive mode or an idlemode.